Io - Voyager 1

A volcanic caldera on Jupiter's moon, Io

Image of possible volcanic calderas on Jupiter's moon Io. The caldera may be
venting gasses, seen as the light patch at left center in this picture.
The dark areas on the caldera floor are thought to be molten sulfur. The
image was taken as Voyager 1 approached Io at a distance of about 130,000 km.
(Voyager 1, P-21286)
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